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Singularity-EOS: Performance Portable Equations of State and Mixed Cell Closures
We present Singularity-EOS, a new performance-portable library for equations of state and related capabilities. Singularity-EOS provides a large set of analytic equations of state, such as the Gruneisen equation of state, and tabulated equation of state data under a unified interface. It also provides support capabilities around these equations of state, such as Python wrappers, solvers for finding pressure-temperature equilibrium between multiple equations of state, and a unique modifier framework, allowing the user to transform a base equation of state, for example by shifting or scaling the specific internal energy. All capabilities are performance portable, meaning they compile and run on both CPU and GPU for a wide variety of architectures.
Evolution of Chemical Conditions and Estimated Plutonium Solubility in the Residual Waste Layer During Post-Closure Aging of Tank 18
This document updates the Eh-pH transitions from grout aging simulations and the plutonium waste release model of Denham (2007, Rev. 1) based on new data. New thermodynamic data for cementitious minerals are used for the grout simulations. Newer thermodynamic data, recommended by plutonium experts (Plutonium Solubility Peer Review Report, LA-UR-12-00079), are used to estimate solubilities of plutonium at various pore water compositions expected during grout aging. In addition, a new grout formula is used in the grout aging simulations and apparent solubilities of coprecipitated plutonium are estimated using data from analysis of Tank 18 residual waste. The conceptual model of waste release and the grout aging simulations are done in a manner similar to that of Denham (2007, Rev. 1). It is assumed that the pore fluid composition passing from the tank grout into the residual waste layer controls the solubility, and hence the waste release concentration of plutonium. Pore volumes of infiltrating fluid of an assumed composition are reacted with a hypothetical grout block using The Geochemist's Workbench{reg_sign} and changes in pore fluid chemistry correspond to the number of pore fluid volumes reacted. As in the earlier document, this results in three states of grout pore fluid composition throughout the simulation period that are termed Reduced Region II, Oxidized Region II, and Oxidized Region III. The one major difference from the earlier document is that pyrite is used to account for reducing capacity of the tank grout rather than pyrrhotite. This poises Eh at -0.47 volts during Reduced Region II. The major transitions in pore fluid composition are shown. Plutonium solubilities are estimated for discrete PuO2(am,hyd) particles and for plutonium coprecipitated with iron phases in the residual waste. Thermodynamic data for plutonium from the Nuclear Energy Agency are used to estimate the solubilities of the discrete particles for the three stages of pore fluid evolution. In Denham (2007, Rev. 1), the solubilities in the oxidized regions were estimated at Eh values in equilibrium with dissolved oxygen. Here, these are considered to be maximum possible solubilities because Eh values are unlikely to be in equilibrium with dissolved oxygen. More realistic Eh values are estimated here and plutonium solubilities calculated at these are considered more realistic. Apparent solubilities of plutonium that coprecipitated with iron phases are estimated from Pu:Fe ratios in Tank 18 residual waste and the solubilities of the host iron phases. The estimated plutonium solubilities are shown. Uncertainties in the grout simulations and plutonium solubility estimates are discussed. The primary uncertainty in the grout simulations is that little is known about the physical state of the grout as it ages. The simulations done here are pertinent to a porous medium, which may or may not be applicable to fractured grout, depending on the degree and nature of the fractures. Other uncertainties that are considered are the assumptions about the reducing capacity imparted by blast furnace slag, the effects of varying dissolved carbon dioxide and oxygen concentrations, and the treatment of silica in the simulations. The primary uncertainty in the estimates of plutonium solubility is that little is known about the exact form of plutonium in the residual waste. Other uncertainties include those inherent in the thermodynamic data, pH variations from those estimated in the grout simulations, the effects of the treatment of silica in the grout simulations, and the effect of varying total dissolved carbonate concentrations. The objective of this document is to update the model for solubility controls on release of plutonium from residual waste in closed F-Area waste tanks. The update is based on new information including a new proposed grout formulation, chemical analysis of Tank 18 samples and more current thermodynamic data for plutonium and grout minerals. In addition, minor changes to the modeling of the grout chemical evolution have been made. It should be noted that the intent is to provide bounding solubilities for plutonium to be used in Performance Assessment modeling rather than trying to identify an exact concentration of plutonium in pore fluids released from a tank at any given time. This document also considers suggestions and opportunities for improvement regarding the plutonium modeling assumptions from the Plutonium Solubility Peer Review Report, LA-UR-12-00079.
Evaluating Radiative Closure in the Middle-to-Upper Troposhere
This project had two general objectives. The first is the characterization and improvement of the radiative transfer parameterization in strongly absorbing water vapor bands, as these strongly absorbing bands dictate the clear sky radiative heating rate. The second is the characterization and improvement of the radiative transfer in cirrus clouds, with emphasis on ensuring that the parameterization of the radiative transfer is consistent and accurate across the spectrum. Both of these objectives are important for understanding the radiative processes in the mid-to-upper troposphere. The research on this project primarily involved analysis of data from the First and Second Radiative Heating in Underexplored Bands Campaigns, RHUBC-I and II. This included a climate model sensitivity study using results from RHUBC-I. The RHUBC experiments are ARM-funded activities that directly address the objectives of this research project. A secondary effort was also conducted that investigated the trends in the long-term (~14 year) dataset collected by the Atmospheric Emitted Radiance Interferometer (AERI) at the ARM Southern Great Plains site. This work, which was primarily done by a post-doc at the University of Wisconsin, Madison under Dr. Turner's direction, uses the only NIST-traceable instrument at the ARM site that has a well-documented calibration and uncertainty performance to investigate long-term trends in the downwelling longwave radiance above this site.
Performance Assessment of Bi-Directional Knotless Tissue-Closure Device in Juvenile Chinook Salmon Surgically Implanted with Acoustic Transmitters, 2010 - Final Report
In 2010, researchers at Pacific Northwest National Laboratory (PNNL) and the University of Washington (UW) conducted a compliance monitoring study—the Lower Columbia River Acoustic Transmitter Investigations of Dam Passage Survival and Associated Metrics 2010 (Carlson et al. in preparation)—for the U.S. Army Corps of Engineers (USACE), Portland District. The purpose of the compliance study was to evaluate juvenile Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) passage routes and survival through the lower three Columbia River hydroelectric facilities as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp; NOAA Fisheries 2008) and the Columbia Basin Fish Accords (Fish Accords; 3 Treaty Tribes and Action Agencies 2008).
Post-Closure Inspection, Sampling, and Maintenance Report for the Salmon, Mississippi, Site Calendar Year 2012
This report summarizes the 2012 annual inspection, sampling, measurement, and maintenance activities performed at the Salmon, Mississippi, Site (Salmon site). The draft Long-Term Surveillance and Maintenance Plan for the Salmon Site, Lamar County, Mississippi (DOE 2007) specifies the submittal of an annual report of site activities with the results of sample analyses. A revised plan is in preparation. The Long-Term Surveillance Plan for the Salmon, Mississippi, Site is intended for release in 2013. The Salmon site consists of 1,470 acres. The site is located in Lamar County, Mississippi, approximately 10 miles west of Purvis, Mississippi, and about 21 miles southwest of Hattiesburg, Mississippi The State of Mississippi owns the surface real estate subject to certain restrictions related to subsurface penetration. The State is the surface operator; the Mississippi Forestry Commission is its agent. The federal government owns the subsurface real estate (including minerals and some surface features), shares right-of-entry easements with the State, and retains rights related to subsurface monitoring. The U.S. Department of Energy (DOE) Office of Legacy Management (LM), a successor agency to the U.S. Atomic Energy Commission, is responsible for the long-term surveillance of the subsurface real estate
Post-Closure Inspection, Sampling, and Maintenance Report for the Salmon, Mississippi, Site Calendar Year 2011
This report summarizes the 2011 annual inspection, sampling, measurement, and maintenance activities performed at the Salmon, Mississippi, Site (Salmon site1). The draft Long-Term Surveillance and Maintenance Plan for the Salmon Site, Lamar County, Mississippi (DOE 2007) specifies the submittal of an annual report of site activities with the results of sample analyses. The Salmon site consists of 1,470 acres. The site is located in Lamar County, Mississippi, approximately 10 miles west of Purvis, Mississippi, and about 21 miles southwest of Hattiesburg, Mississippi.
Interface-aware sub-scale dynamics closure model for multimaterial cells in Lagrangian gas dynamics
Abstract Not Provided
Genetic Analysis of Ca 2+ Priming in Arabidopsis Guard Cell Stomatal Closure in Response to the Drought Hormone Abscisic Acid
A primary objective of modern agriculture and biofuel production is to utilize arable land to its fullest potential. However, sub-optimal growing conditions—arising from abiotic stresses such as drought, soil salinity, low humidity, cold, and heat—reduce crop yield and quality. Optimal yield under both stressed and non-stressed conditions requires the plant to activate coping mechanisms at a level commensurate with the severity of the drought stress. The osmotic sensors and associated regulatory mechanisms that initiate drought- and salt-tolerance responses in plants are largely unknown. This research aimed to identify and characterize these initial sensory components.
Institutional Computing use for CASL Studies of Multiphase Momentum Closure
No abstract provided.
Final Monitoring Plan for Site Closure at Inman, Kansas
Inman, Kansas, is a rural town located in southwest McPherson County, in sections 8, 9, 16, and 17, Township 21 South, Range 4 West (Figure 1.1). There are 1,377 people in 513 households, as of the census of 2010. The Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA), operated a grain storage facility at the southern edge of the city of Inman, Kansas, from 1954 to 1965. During this time, commercial grain fumigants containing carbon tetrachloride were in common use by the grain storage industry to preserve grain in their facilities. In 1997, trace to low levels of carbon tetrachloride (below the maximum contamination level [MCL] of 5.0 μg/L) were detected in three private wells near the former grain storage facility at Inman, as part of a statewide USDA private well sampling program that was implemented by the Kansas Department of Health and Environment (KDHE) near former CCC/USDA facilities. No public water supply wells were identified within 1 mi of the town by the KDHE in 1998. Carbon tetrachloride is the contaminant of primary concern at sites associated with grain storage operations. To determine whether the former CCC/USDA facility at Inman is a potential contaminant source and its possible relationship to the carbon tetrachloride contamination in groundwater, the CCC/USDA agreed to conduct a multi-phase investigation at Inman. The investigation was performed by the Environmental Science Division of Argonne National Laboratory in accordance with the Intergovernmental Agreement between the KDHE and the Farm Service Agency of the USDA.
Continuous Improvement of Closures for PWR and BWR Simulations
The purpose of the current report is to document the progress of research conducted at RPI between October 1, 2016 and February 28, 2017.
Corrective Action Management Unit Report of Post-Closure Care Activities Calendar Year 2016.
The Corrective Action Management Unit (CAMU) at Sandia National Laboratories, New Mexico (SNL/NM) consisted of a containment cell, two treatment systems, four associated waste staging and storage areas, and support areas; all were used for management of remediation wastes between 1997 and 2003.
Boiling Closure Model Validation/Development Effort with TAMU Experimental Data
This report describes a model validation and developmental effort in INL based on the analysis of experimental data taken from TAMU subcooled flow boiling facility. This report first describes briefly the test loop, experimental strategy, measurement techniques, data quality achieved, and test boundary conditions. Then, two main topics are discussed based on the experimental observation, bubble departure frequency and sliding bubble characteristics. The comparison of experimental data with the prediction of bubble departure frequency models shows that the predictive capability of existing models depends strongly on flow conditions. Also, the best performance region of each bubble departure frequency model could be determined from this analysis. Another critical achievement through this study is that the limitation of existing CFD boiling models dealing with sliding bubble effect was clearly identified. Specifically, the experimental observation indicates that the wall area influenced by sliding bubbles is not just a function of bubble size, but also depends strongly on sliding bubble trajectory and sliding distance. As a result, the bubble influence factor ( K ) for the small size of sliding bubbles was often found substantially higher than those reported in literature. In this regard, an effort is currently being made in INL to develop a new model to predict the sliding bubble effect on wall heat transfer based on the insight achieved from TAMU subcooled flow boiling experiment.
CO2 Sequestration Saline Aquifer Well Closure
Materials of construction to plug and abandon a well for underground storage of CO2. To access the model referenced in the report, please visit https://www.netl.doe.gov/energy-analysis/details?id=184B416C-9D9C-4D43-ACF3-4A8B9F0463D6
Saline Aquifer Well Construction, Installation and Closure Assembly
This unit process models the assembly of the different well types required for a saline aquifer being used for CO2 sequestration. To access the model referenced in the report, please visit https://www.netl.doe.gov/energy-analysis/details?id=8BFC8632-B7E5-4A0A-AF58-A54CC2D3AA4C